Steve Conley
EF0
I believe Newton's is at the airport, and based on my boss's station at home, and my truck (ok, not the most accurate device <grin>), it seems to be pretty accurate.
Dewpoints in IA/MN
- Thread starter Josh Richardson
- Start date
Rob Wadsworth
EF5
The evapotranspiration rate of corn/soybeans in Iowa is in an extreme point of their growth phase. I'm sure these numbers also translate into the nearby towns.
Sounds like the kind of day where people shut everything off - except for their air conditioners and de-humidifiers. A cool basement would also be a proper place to be - so long as a de-humidifier is working. I've been in IA when temps were similar to these.
Yeow!
Sounds like the kind of day where people shut everything off - except for their air conditioners and de-humidifiers. A cool basement would also be a proper place to be - so long as a de-humidifier is working. I've been in IA when temps were similar to these.
Yeow!
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Josh Richardson
EF4
I think this thread gets brought up every year but since someone asked about record dewpoints...the highest I've seen around here was 101/87 over at Onawa. Like Jeff mentioned earlier though there are many of these stations planted in corn fields and its pretty easy to determine which numbers are skewed and which aren't. I would say with confidence though that the average dews around here were still near 80, maybe 78 or 79. So heat indices have been hovering near the 105 mark in many places. I did notice Creston IA earlier was up to 95/79, 113 heat index.
This linear MCS moving through is a blessing. The temperature in Ames dropped from about 94 to about 70 when the gust front moved through. The dewpoint only went down to about 68 though 
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http://mesonet.agron.iastate.edu/plotting/iemcc/
. http://mesonet.agron.iastate.edu/plotting/iemcc/
Steve Conley
EF0
Agree with the blessing, 76 in Newton now.
cstrunk
EF3
I have had to work outside yesterday and today. I immediately started sweating whenever I stepped outside. Agreed about the squall line, much nicer outside now!
We have been kind of lucky in terms of nice weather (bad in terms of storm chaser weather!!) with temps in the 60's and 70's for quite a while. Now we're paying for it with the heat!
We have been kind of lucky in terms of nice weather (bad in terms of storm chaser weather!!) with temps in the 60's and 70's for quite a while. Now we're paying for it with the heat!
mikegeukes
EF5
I usually like to compare the ASOS stations to AWOS stations.
Often the ASOS dewpoints are a tad lower than the AWOS Stations
in situations during June and July when evapotranspiration is occurring.
Iowa ASOS Stations:
Ames, Burlington, Cedar Rapids, Davenport, Des Moines, Dubuque,
Estherville, Iowa City, Lamoni, Marsalltown, Mason City, Ottumwa,
Sioux City, Spencer, Waterloo.
Mike
Often the ASOS dewpoints are a tad lower than the AWOS Stations
in situations during June and July when evapotranspiration is occurring.
Iowa ASOS Stations:
Ames, Burlington, Cedar Rapids, Davenport, Des Moines, Dubuque,
Estherville, Iowa City, Lamoni, Marsalltown, Mason City, Ottumwa,
Sioux City, Spencer, Waterloo.
Mike
Joel Wright
EF5
With the hybrid corn/soybeans nowadays it seems as if the evapotranspiration is worse. Corn seems to grow taller every season around here. Kind of makes you wonder lol. Either way, living in the cornbelt is an interesting experience this time of year. If you've ever been near a cornfield on a day like today you'll understand how the dewpoints can get so high. It's amazing how much moisture those plants release into the surrounding air. It's damn near suffocating.
Mike Hollingshead
Earlier today while chasing in nw IA I noticed several stations reporting mid-80 dews. Kind of doubt they are all way off. Top I saw was 96/86. I did see that 101/87 at Onawa mentioned, a few years ago. You have hilly terrain, corn, and that time recent rain and a left over boundary nearby.
TWC mentioned one in Saudi or some desert over there the other day. Some record or something. 108/93 I think. Temp was 108, I forget the TD might have been over 93.
TWC mentioned one in Saudi or some desert over there the other day. Some record or something. 108/93 I think. Temp was 108, I forget the TD might have been over 93.
Dustin Wilcox
EF5
When the corn is silking it uses approximately .30" of water a day...
GlennMartin
EF0
You are right about the corn. June-August on calm nights you can often see thick ground fog pool around the cornfields, I first noticed this as a young man driving through the cornfields of northern Ohio and Indiana sometimes the eerie fog was suddenly so thick you had to slow to a crawl.
We're still 3-4 weeks from peak transpiration from the corn... Silking in IA/MN is usually mid-July, later as you go north. Sweet corn is of course a bit earlier, but there isn't as much.
It's always hard this time of year to do CAPE numbers because you can't just use the surface ob because that really soupy air is a fairly shallow layer, so it isn't all realized by a storm. As far as the people though, yeah, it's miserable. You can sit next to a corn field and feel the moisture flowing out on a calm evening.
It's always hard this time of year to do CAPE numbers because you can't just use the surface ob because that really soupy air is a fairly shallow layer, so it isn't all realized by a storm. As far as the people though, yeah, it's miserable. You can sit next to a corn field and feel the moisture flowing out on a calm evening.
Jason McKittrick
EF3
Highest dewpoints, I looked this one up a couple of years ago. The worlds highest was 96 recorded in the Amazon. I have seen 90's on a few occasions in the Persian Gulf since then. I do not remember the highest US dewpoint seems like it was 92. I did however see, during the July heat wave in 1995 Appleton, Wisconsin reach 103/90. That is the highest dew I have ever seen in the US. The highest dew I have experienced hear in Omaha was on July 15, 1988, the day of the Council Bluffs tornado. The airport hear had an observation of 92/84 just prior to that event.
It is funny to watch the mets on the weather channel try and talk about dewpoints in the cornbelt. The think they live in a humid place and they have never seen 80 degree dewpoints down there in Atlanta, or at least it is very rare. Yesterday they were talking about how humid it was in the cornbelt with "dewpoints in the upper 60's and lower 70's". Dewpoints at that time were actually in the upper 70's and lower 80's most places. Guess they didn't believe there eyes. Anyone who lives in the cornbelt can tell you that the gulf coast is not nearly as humid as a cornfield in July.
It is funny to watch the mets on the weather channel try and talk about dewpoints in the cornbelt. The think they live in a humid place and they have never seen 80 degree dewpoints down there in Atlanta, or at least it is very rare. Yesterday they were talking about how humid it was in the cornbelt with "dewpoints in the upper 60's and lower 70's". Dewpoints at that time were actually in the upper 70's and lower 80's most places. Guess they didn't believe there eyes. Anyone who lives in the cornbelt can tell you that the gulf coast is not nearly as humid as a cornfield in July.
